ORIGINAL: Lnewqban
Isn't a smaller diameter tube the best way to keep the rod centered in the tube?
Yes, but then, the friction would be higher, especially after some time, after which rust and dirt accumulates.
In my opinion, not the best system in the world anyway.
I totally agree with you but the larger tubes are what are supplied with some of the kits. When rigging most of my kits with my own inventory I use the Du-Bro plastic tubes with steel rods and have never had a problem even with models that are 20+ years old.
Cheers